Axle cushioning assembly for wheels on construction equipment

ABSTRACT

An axle cushioning assembly for absorbing the shock load forces transferred between the wheels and axles of construction equipment. Elastomer sleeves are positioned between an inner sleeve mounted on the axle and an outer concentric barrel mounted to the wheel. Annular retainer means compressably holds the elastomer sleeves in position and provides relief openings permitting limited yieldable extrusion or deformation of the elastomer material under wheel loading.

United States Patent [191 Caron et al.

AXLE CUSHIONING ASSEMBLY FOR WHEELS ON CONSTRUCTION EQUIPMENT Inventors: Fred Joseph Caron, Citrus Heights; James Oliver Caron, Sacramento; George Carrol Gray, Fair Oaks, all of Calif.

Caron Compactor Co., West Sacramento, Calif.

Filed: Aug. 12, 1970 Appl. No.: 63,122

Assignee:

US. Cl ..152/49, 94/50 PR, 301/1 Int. Cl. ..B60b 9/12 Field of Search ..l52/7, 40-50;

References Cited UNITED STATES PATENTS 9/1925 Morand ..152/49 Primary ExaminerJames B. Marbert Assistant Examiner-D. W. Keen AttorneyFlehr, Hohbach, Test, Albritton & Herbert 5 7] ABSTRACT An axle cushioning assembly for absorbing the shock load forces transferred between the wheels and axles of construction equipment. Elastomer sleeves are positioned between an inner sleeve mounted on the axle and an outer concentric barrel mounted to the wheel. Annular retainer means compressably holds the elastomer sleeves in position and provides relief openings permitting limited yieldable extrusion or deformation of the elastomer material under wheel loading.

5 Claims, 4 Drawing Figures PATENTED FEB 2 7 I973 SHEET 10F 2 N M a? w 9 i P i Mi! 0 five r un r mac 4 nan AXLE CUSHIONING ASSEMBLY FOR WHEELS ON CONSTRUCTION EQUIPMENT CROSS REFERENCE TO RELATED APPLICATION Reference is made to co-pending application Ser. No. 59,432, filed July 30, 1970, now abandoned entitled Pull-Type Compaction Wheel.

BACKGROUND OF THE INVENTION This invention in general relates to the construction equipment field, and in particular relates to heavy duty construction equipment or vehicles incorporating rigid wheels, such as the compactor wheels used for compacting earth and refuse.

Heavy duty construction vehicles commonly employ rigid wheels for use as roller, compaction, or tamper wheels to roll, compact, crush, grind, and break-up earth and refuse material in sanitary land fill operations and the like. The wheels may either be provided with smooth outer rims, such as for rolling a smooth surface, or with cleats or tamper members secured to the wheel rim, such as outwardly projecting sheepsfoot shanks and caps or wedge-shaped cleats and the like. These wheels commonly comprise a large hollow steel drum mounted about an axle which in turn is mounted for rotation on pillow blocks of the vehicle frame. Ballast compartments are conventionally provided within the drum for holding a quantity of wet sand or water ballast to increase the compaction or crushing pressure. The vehicles may either be self-propelled by means of directly powering the compaction wheels, or may be of the pull-type where a separate prime mover such as a crawler bulldozer or rubber tired tractor is used to pull or push the vehicle.

A recurring problem encountered with construction equipment of the type described has been in the failure of the wheel axles due to the severe shock loads transferred between the wheel and axle as the vehicle operates over the earth or refuse fill. These shock loads are generated as the heavy, rigid wheels are pulled at high speeds over undulations in the fill, ruts, large rocks, boulders, stumps, or other obstructions along the path of travel. The shock loading has been found to' be so severe that even large diameter axles of high strength steel will fail in shear resulting in expensive downtime for replacement and repair. Construction equipment of the type incorporating wheels with large diameter rubber tires provide the required axle cushioning under heavy shock loading, but the tires do not have the necessary rigidity for use in compaction operations where high energy forces must be delivered to properly break up and compact the earth or refuse fill. Accordingly, the need has been recognized for means which will adequately protect and cushion the axles on rigid wheels of heavy duty construction equipment from destructive shock forces.

OBJECTS AND SUMMARY OF THE INVENTION It is a general object of the invention to provide an improved wheel for construction equipment incorporating axle cushioning means to minimize the effects of shock loads transferred to wheel axles on the equipment.

Another object is to provide axle cushioning means for the rigid wheels of heavy duty construction vehicles which is effective to absorb the severe shock loads encountered during vehicle operation and protect the wheel axles from destructive shear stresses.

Another object is to provide an axle cushioning assembly for absorbing shock loading on the axles of rigid wheels of heavy-duty construction equipment such as earth and refuse fill compactors.

Another object is to provide an axle cushioning assembly incorporating at least one elastomer sleeve in a novel arrangement to absorb the shock loads transferred between the rigid wheel and wheel axle of construction vehicles.

The foregoing and other objects and advantages of the invention are provided by a novel axle cushioning assembly incorporating a rigid inner sleeve concentric with and mounted on the wheel axle. An outer barrel mounted for rotation with the wheel is radially spaced from the inner sleeve to define an annular cavity and at least one sleeve of an elastomer material is mounted within this cavity to absorb the shock loading transferred from the wheel to the axle. Annular retainer rings compressably retain the elastomer sleeves within the cavity and define annular openings at the sleeve ends to permit limited yieldable extrusion or deformation of the elastomer material as shock load forces are imposed on the wheel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of one preferred embodiment of a heavy duty earth and refuse fill compaction machine according to the invention;

FIG. 2 is an enlarged, fragmentary cross-sectional view taken along the line 2-2 of the FIG. 1.

FIG. 3 is a view similar to FIG. 2 illustrating another preferred embodiment of the invention; and

FIG. 4 is a view similar to FIGS. 2 and 3 illustrating another preferred embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawings, FIG. 1 illustrates generally at 10 a heavy duty construction vehicle of the type comprising an earth and refuse fill compaction machine. Compaction machine 10 includes a main frame 12 mounted on a pair of side-by-side perimeter frames 14, one of which is illustrated, adapted for oscillation movement about longitudinal axes on trunnious 16. Each of the perimeter frames 14 in turn are mounted on pairs of independently journaled rigid compaction wheels 18, 20. Compaction machine 10 is of the pull-type adapted to be pulled by a prime mover through hitch 22 provided at the front end of the main frame, and a pusher plate 24 is provided at the rear end for receiving reaction forces from a pusher vehicle.

The pair of perimeter frames 14 are substantially identical and their construction and operation are detailed in the above referenced application entitled Pull-Type Compaction Wheel." It will here suffice to briefly describe one of the perimeter frame, which includes a pair of longitudinally extending box frame members 26, 28 and central box frame member 30 secured to end members 32, 34 which in turn are mounted for oscillatory movement on trunnious 16 by means of split coupler assemblies 36, 38. While a pair of perimeter frames 14 are described for the machine and a pair of wheels 18, are described as mounted on each perimeter frame, it is understood that the number of wheels and perimeter frames can be varied depending upon particular requirements and specifications. For example, a compaction machine incorporating a single perimeter frame with two compaction wheels could be provided for small scale earth and refuse fill operations.

The rigid compaction wheels 18, 20 are of substantially identical construction and operation and it will suffice to describe that for the outboard wheel 18. This wheel comprises a hollow cylinder 40 defining a wheel rim. A pair of axially spaced annular end plates 42, 44 are secured by suitable means such as welding within cylinder 40. The end plates in turn are mounted as by welding to an elongate hollow barrel 46. The wheel rim, end plates and barrel together define a ballast compartment 48 for containing a suitable ballast such as wet sand or water. The ballast is introduced into the compartment through suitable fittings, not shown, provided in the end plates. A plurality of ground engaging cleats 49 are circumferentially arranged in plural sideby-side rows, shown as three rows, on the wheel rim surface.

The wheel 18 is mounted for independent rotation on the perimeter frame about axle shaft 50 by means of a pair of roller bearing pillow blocks 52, 54 mounted belo w respective frame members 28, 30. An outer bearing cover 56 is mounted on frame member 28 to protect pillow block 52 and a double bearing cover 58 is mounted below frame member 30 to protect the pair of inboard pillow blocks.

The axle cushioning means for wheel 18 comprises a pair of elastomer sleeves 60, 62 of a suitable material such as rubber. A natural rubber material having a tensile strength in the range of 3500-4000 psi, a 60 durometer value, and with a high heat dissipation factor may be advantageously utilized. The elastomer sleeves are mounted over an elongate inner sleeve 64 which in turn is mounted on axle shaft 50. The two elastomer sleeves are positioned within the annular cavity formed between the inner sleeve and outer barrel by means of a common inner retainer ring 66 secured at the mid point of inner sleeve 64, and a pair of outer retainer rings 68, 70 secured to respective ends of barrel 46. The elastomer sleeves are assembled under compression between the retainers 66, 68 and 70 to provide a tight fitting relationship between the outer barrel, elastomer sleeves and inner sleeves. Inner retainer ring 66 is radially spaced from the inside surface of barrel 46 to define an annular relief opening at the interface between the two elastomer sleeves. Similarly, the two end position retainer rings 68, 70 are radially spaced from innersleeve 64 defining annular relief openings at respective cavity end openings. The relief openings permit limited yieldable extrusion or deformation of the elastomer sleeves both to accommodate expansion, extrusion or deformation of the elastomer material when compressed during assembly, and while shock load forces received from the wheel are absorbed by the sleeves 60, 62. The edges 71, 73 of the inner end faces of the elastomer sleeves are beveled adjacent the common inner relief opening and the edges 75, 77 of the sleeve outer end faces are beveled adjacent respective outer relief openings so that, after assembly and compression of the elastomer sleeves, the inner and outer end faces of these sleeves present a substantially flat surface to the respective relief openings. For purposes of clarity and understanding all elastomer sleeves are illustrated in the drawings in their uncompressed condition.

The elements of the axle cushioning assembly for the embodiment f illustrated in FIG. 2 are assembled together as follows. lnner sleeve 64 together with its center position retainer ring 66 are inserted within barrel 46 of the wheel. The two elastomer sleeves 60, 62 in their relaxed or uncompressed condition are inserted within the cavity defined between the inner sleeve and outer barrel. A suitable lubricant, such as soap, may be applied to the surfaces of the sleeves and barrel to facilitate this step. A suitable jig or fixture, not shown, is then used to inwardly compress or squeeze the sleeves 60, 62 which expand somewhat to provide close fitting contact between the inner sleeve and outer barrel. With the sleeves compressed end retainer rings 68, are then positioned as illustrated and secured in place by suitable means such as welding to retain the elastomer sleeves in the compressed condition. Axle shaft 50 is then inserted within inner sleeve 64 and the wheel is then mounted on perimeter frame 14 with pillow blocks 52, 54 locking the axle in position. Shims 72, 74 are provided to take up axial slack between the pillow blocks and inner sleeve 64.

In the use and operation of the invention for the illustrated compaction machine 10 the shock forces received by wheel 18 as the machine is pulled or pushed over the the earth or refuse fill are transmitted into and largely absorbed by the elastomer sleeves 60, 62 to protect the axle from destructive shear stresses. The energy imparted to the sleeves in this manner causes the elastomer material to undergo a limited and yieldable extrusion or deformation at the relief openings of the retainer rings 66-70, with the material returning to its normal position as the wheel loading is reduced or relieved.

HO. 3 illustrates another preferred embodiment of the invention incorporating an axle cushioning means for a compactor wheel 76 of the sheepsfoot type. Compaction wheel 76 includes a relatively small diameter hollow cylinder 78 defining a wheel rim with annular end plates 80, 82 secured thereto. A plurality of radially outwardly projecting sheepsfoot shanks 84 are secured to the outer surface of cylinder 78 in side-byside rows, and the distal ends of these shanks are formed with convention sheepsfoot tampers, now shown. An elongate outer barrel 86 is mounted concentric with and between end plates 80, 82 and an inner sleeve 88 is positioned within and radially spaced from barrel 86 to define an annular cavity. A pair of elastomer sleeves 90, 92 are positioned within this cavity with their inner ends in abutting relationship against a central retainer ring 94 secured to sleeve 88. End position annular retainer rings 96, 98 are secured to the ends of barrel 86 to compressably hold the elastomer sleeves in position. Retainer ring 94 is radially spaced from the inside surface of barrel 86 to define an annular relief opening, and end retainer rings 96, 98 are likewise radially spaced from inner sleeve 88 to define annular relief openings at the outer ends of the elastomer sleeves. The elastomer sleeve inner end edges 100, 102 are beveled adjacent the common inner relief opening and the sleeve outer end edges 104, 106 are beveled adjacent respective outer relief openings. Inner sleeve 88 is mounted over axle shaft 108 which in turn is mounted by means of a pair of pillow blocks 110, 112 to frame members 114, 116 on a compaction vehicle perimeter frame of the type previously described.

The elements of the axle cushioning assembly for wheel 76 are assembled in a manner similar to that described above for the embodiment of FIG. 2. In use, the shock load forces received by the sheepsfoot shanks 84 as wheel 76 traverses the earth or refuse fill are transmitted into and largelyabsorbed by the elastomer material of sleeves 90, 92. The energy of these forces imparted to the elastomer sleeves causes the ends thereof to undergo a limited yieldable extrusion or deformation into the relief openings in the manner previously described, thereby protecting axis shaft 108 from the severe shock loads and shear stresses which otherwise would lead to early failure of the axle.

FIG. 4 illustrates another preferred embodiment of the invention incorporating a compaction wheel 118 of the type described in connection with the embodiment of FIG. 2 but with a relatively greater tread width to accommodate up to five or more circumferential rows of compaction cleats as compared to the previously described compactor wheel 18 of a smaller tread width. Wheel 118 comprises a hollow cylinder 120 defining a wheel rim. A plurality of compactor cleats 122 are circumferentially arranged in five side-by-side rows on wheel rim. A pair of annular end plates 124, 126 and an annular central diaphragm 128 are secured at axially spaced positions within cylinder 120. An elongate barrel 130 is mounted concentrically within the end plates and diaphragm. An inner sleeve 132 is positioned within barrel 130 and defines an annular cavity therewith. A pair of annular retainer rings 134, 136 are mounted at axially spaced positions to inner sleeve 132, and a pair of elastomer sleeves 138, 140 are mounted at the cavity ends in abutting relationship with respective retainer rings 134, 136. A pair of end positioned retainer rings 142, 144 mounted to the ends of barrel 130 compressably retain the elastomer sleeves in position. Inner retainer rings 134, 136 are radially spaced from barrel 130 to define inner relief openings therewith, and outer retainer rings 142, 144 are axially spaced from inner sleeve 132 to define end relief openings therewith. The inner end edges 146, 148 and the outer end edges 150, 152 of the elastomer sleeves are beveled adjacent respective relief openings to present a substantially flat surface therewith with the elastomer sleeves compressed in assembled relationship. Inner sleeve 132 is mounted on axle shaft 154 which in turn is mounted by means of pillow blocks 156, 158 to frame members 160, 162 of a compaction vehicle perimeter frame of the type described above.

The elements of the axle cushioning assembly for compaction wheel 118 are assembled in a manner similar to that described above for the embodiment of FIG. 2. In operation the shock load forces received by wheel 118 as the machine traverses the earth and refuse fill are absorbed in the material of the elastomer sleeves 138, 140 to protect axle shaft 154 from severe shear stresses. The energy imparted to the elastomer material by these forces causes a limited yieldable extrusion or deformation of the elastomer material into the relief openings in the manner described above.

While the embodiments herein are at present considered to be preferred, it will be understood that numerous variations and modifications may be made therein by those skilled in the art and it is intended to cover in the appended claims all such variations and modifications as fall within the true spirit and scope of the invention.

We claim:

1. For use with a heavy-duty construction vehicle the combination of a vehicle frame, at least a pair of spaced apart bearing means fixedly mounted on said frame with no intermediate support or cushioning means disposed between said frame and bearing means, a wheel axle rotatably mounted on said bearing means, a ground engaging rigid wheel, and cushioning assembly means interposed between said wheel and axle, the cushioning assembly means comprising an inner sleeve concentric with and fixedly mounted about the wheel axle, an outer barrel concentric with the inner sleeve and radially spaced therefrom to define an elongate annular cavity opened toward each end thereof, the outer barrel being fixedly mounted for rotation with the .wheel, at least one annular elongate sleeve of an elastomer material mounted under axial compression in the cavity for tight fitting frictional gripping engagement between the barrel and inner sleeve to absorb shock loading transmitted from the wheel to the axle, and to transfer torque forces therebetween, said elastomer sleeve being formed with opposed end faces which are bevelled in an uncompressed condition of the elastomer sleeve, retainer means mounted at respective ends of the elastomer sleeve to retain the same under said axial compression within the cavity, the retainer means defining annular relief openings at the respective elastomer sleeve end faces to permit limited yieldable extrusion of the elastomer material into the relief openings as shock load forces are imposed on the wheel.

2. The axle cushioning assembly of claim 1 in which the elastomer material is rubber.

3. The axle cushioning assembly of claim 1 in which the retainer means comprises a pair of retainer rings, each ring being mounted to a respective end of the barrel and radially spaced from the inner sleeve to define said relief openings.

4. The axle cushioning assembly of claim 1 in which a pair of said elastomer sleeves are mounted in end-toend relationship, and said retainer means includes centrally positioned retainer means mounted between the pair of sleeves and defining an inner annular relief opening between the barrel and inner sleeve to permit limited yieldable extrusion of the material of the two elastomer sleeves under loading from the wheel.

5. The axle cushioning assembly of claim 4 in which the pair of elastomer sleeves are axially spaced apart along the length of the axle, and said centrally positioned retainer means comprises a pair of axially spaced apart retainer rings, each ring being mounted to the inner sleeve adjacent an inner end of a respective elastomer sleeve. 

1. For use with a heavy-duty construction vehicle the combination of a vehicle frame, at least a pair of spaced apart bearing means fixedly mounted on said frame with no intermediate support or cushioning means disposed between said frame and bearing means, a wheel axle rotatably mounted on said bearing means, a ground engaging rigid wheel, and cushioning assembly means interposed between said wheel and axle, the cushioning assembly means comprising an inner sleeve concentric with and fixedly mounted about the wheel axle, an outer barrel concentric with the inner sleeve and radially spaced therefrom to define an elongate annular cavity opened toward each end thereof, the outer barrel being fixedly mounted for rotation with the wheel, at least one annular elongate sleeve of an elastomer material mounted under axial compression in the cavity for tight fitting frictional gripping engagement between the barrel and inner sleeve to absorb shock loading transmitted from the wheel to the axle, and to transfer torque forces therebetween, said elastomer sleeve being formed with opposed end faces which are bevelled in an uncompressed condition of the elastomer sleeve, retainer means mounted at respective ends of the elastomer sleeve to retain the same under said axial compression within the cavity, the retainer means defining annular relief openings at the respective elastomer sleeve end faces to permit limited yieldable extrusion of the elastomer material into the relief openings as shock load forces are imposed on the wheel.
 2. The axle cushioning assembly of claim 1 in which the elastomer material is rubber.
 3. The axle cushioning assembly of claim 1 in which the retainer means comprises a pair of retainer rings, each ring being mounted to a respective end of the barrel and radially spaced from the inner sleeve to define said relief openings.
 4. The axle cushioning assembly of claim 1 in which a pair of said elastomer sleeves are mounted in end-to-end relationship, and said retainer means includes centrally positioned retainer means mounted between the pair of sleeves and defining an inner annular relief opening between the barrel and inner sleeve to permit limited yieldable extrusion of the material of the two elastomer sleeves under loading from the wheel.
 5. The axle cushioning assembly of claim 4 in which the pair of elastomer sleeves are axially spaced apart along the length of the axle, and said centrally positioned retainer means comprises a pair of axially spaced apart retainer rings, each ring being mounted to the inner sleeve adjacent an inner end of a respective elastomer sleeve. 